Letrozole more efficacious than clomiphene for infertility treatment among individuals with polycystic ovarian syndrome

Reference

Liu Z, Geng Y, Huang Y, et al. Letrozole compared with clomiphene citrate for polycystic ovarian syndrome. Obstet Gynecol 2023;141(3):523-534.

Synopsis

These authors conducted a meta-analysis of randomized controlled trials (N = 29 with 3952 participants and 7633 ovulation induction cycles) to compare the effect of letrozole and clomiphene citrate on fertility among individuals with polycystic ovarian syndrome (PCOS). They included studies that met the criteria of diagnosis of PCOS based on the Rotterdam 2003 criteria, had timed intercourse or insemination, and reported at least 1 of the 3 outcomes of interest. Seven studies were graded as having high risk of bias to one or more of the following: quasi-randomization (n = 3), lack of fully described allocation concealment (n = 3), lack of masking (n = 6), or differences between groups in duration of infertility (n = 1). Meta-analysis for all primary outcomes favored letrozole; ovulation induction rate (22 studies with 6862 participants; 67% vs 59%; relative risk [RR] 1.14; 95% CI 1.06 - 1.21; P <.001), pregnancy rate (28 studies with 3936 participants; 35% vs 23%; RR 1.48; 1.34 - 1.63, P < .001), and live birth rate (8 studies with 1725 participants; 33% vs 22%; RR 1.49; 1.27 - 1.74; P < .001). The authors judged the certainty of evidence to be low for ovulation induction rate, and moderate for both pregnancy and live birth rate.